type of aluminum in soda cans on carbonated soft drink cans needs lightness and strength, and the popular choices are “3003 aluminum alloy” and “5005 aluminum alloy”. According to the Aluminum Association, the 3003 alloy is approximately 2.7g/cm³ weight and 0.2mm thick in order to provide 1200psi tensile strength, 65% lighter than regular steel cans. More than 70% of the world’s beverage cans use this material, such as Coca-Cola’s 100% recyclable tank launched in 2023, which reduces the thickness of the tank wall to 0.18mm through the application of laser welding technology and weighs only 11.3 grams per tank (Progress in Aluminum Processing Technology 2024).
5005 aluminum alloy since magnesium has been incorporated, corrosion resistance enhanced by 30%, especially for carbon dioxide-containing drinks. Kirin Beverage Company in Japan tested and discovered that tank 5005 was structurally sound for up to 5 years under freezing temperatures, and the gap expansion rate was only 0.02mm/year, significantly lower than the 0.08mm/year of alloy 3003 (International Aluminum Journal 2023 study).
According to the observation of production efficiency, 3003 alloy with high electrical conductivity (approximately 37.7MS/m), used in high-speed rolling molding, can reach 200 tanks/minute, power consumption during production decreases by 22%. According to data from Nanshan Aluminum Industry, China’s leading aluminum profile enterprise, the yield rate of its “very thin aluminum can” production line has already achieved 99.3%, and 18,500 standard cans can be made per ton of raw materials (China Aluminum Industry Annual Report 2024).
As for corrosion resistance testing, the US FDA requires that beverage cans undergo 500 hours of salt spray testing, and the surface oxidation of alloy 3003 under this test is 12μm, while the 5005 alloy without anodizing is 8μm (Food Contact Material Safety Standard 2022). The EU environmental protection directive requires that 95% recovery be attained in all drink cans by 2030, and 3003 alloy has become the mainstream material based on convenience in sorting and recycling.
The latest technological developments are in “double-layer composite aluminum foil” technology, for example, Boston Scientific’s “AluFoil” series extending tank life by 15 years with nanoscale ceramic coating for mineral water packaging with severe transportation conditions (Frontiers in Materials Science 2024). Briefly, 3003 and 5005 alloys constitute the fundamental material of the modern beverage can, and in the future, as the proportion of recycled aluminum (the world will be up to 75% by 2030) increases, material recycling purity will be a key indicator.